Using a room as a server room, there can be computing machines such as servers installed in the room. Providing the computing machines are servers, for instance, such the server room is referred to as a data center. Recent introduction of IT is accompanied by increase in number of such data centers, as well as increases in numbers of computing machines installed in data centers.
Such computing machines dissipate heat when working. As computing machines installed in a server room increase in number, the entire dissipation of heat in the server room increases, so there are advancing developments of air conditioning apparatuses, as well as cooler equipment for supplying cold air into a server room, thereby cooling computing machines.
On the other hand, at server rooms such as data centers, there is such a design as intended for use of a service of power from a commercial power source, and besides, for use of a service of power from an uninterruptible power supply (UPS) in emergencies such as power interruption including interruption of the service of power from the commercial power source. However, for air conditioning apparatuses used for cooling server rooms in the past, there was no consideration made of cooling a server room in such an emergency.